Given the iconic nature of Mr Aldrin's fame, the idea that anybody other than him would have any input into his rates is perhaps a little naive; basically you either pay what he asks, or he won't be coming. (Let's face it, you're not going to get Neil Armstrong to come instead, are you? )
You have access to details of Mr Aldrin's financials? How are you in a position to judge that "he clearly doesn't" need the money? If nothing else, since he has recently filed for divorce in California, one can suspect that however much money he has (or that you think he has) is about to be rather diminished.
Â£225 is a good price for BUZZ. I paid more than that in the states two years ago. If you think it's too much don't pay it!!!!!!

This is my second show and after a 320 mile round trip it was worth every mile got to meet Charlie Duke (he signed my apollo 16 space capsule) Bruce McCandless and Helen sharman OBE. Brilliant, good show loved all the stands as well.